Carlton Cole Magee designed the original parking meter in 1935. The parking meter's purpose was to generate revenue and control traffic. The majority of parking meters in use today use the Magee design. Throughout the years since Magee's design an effort has been made to provide an automatic reset system for parking meters. It has become accepted that such an embodiment would substantially increase revenues 50% to 200%.
Throughout the years municipalities have requested specific evolutionary changes for improving the parking meter. The major changes relate to reducing pilferage, increasing revenue, and lowering operating costs in light of a $2.3 billion annual U.S.A. revenue stream.
The prior art teaches means to reduce pilferage including advanced tumbler key locks and digital security codes. The present invention combines the best advanced tumbler key lock with a unique algorithmic key for each parking meter. The key is based on the total of the last three coin collection counts. Furthermore, a portable terminal creates an audit trail for coins collected.
For increasing revenue the prior art teaches maximum revenue producing (MRP) parking meters. Various vehicle detection means noted below provide the automatic reset of the unexpired time to zero upon the vehicle's departure. However, problems exist with the prior art in distinguishing pedestrians from vehicles and/or distinguishing plastic vehicles. The present invention provides exact vehicle to parking meter distance calculations using an ultrasonic sensor. Additionally the present invention uses a window concept to discern pedestrians from parked cars. This method eliminates pedestrian/vehicle confusion and readily senses plastic or metal vehicles.
In order to reduce operating costs the present invention utilizes a low power (under 250 milliamps) design, with a sleep mode real time computer, and a solar recharger. A seven year expected battery life is forecast.
In order to best view the advantages of the present invention a summary of the most relevant prior art follows below.